Rubber draft gear



Jaun 8, 1957 D. s. CAMPBELL RUBBER DRAFT GEAR 4 Shee'ts-Sheet 1 Filed May 4, 1953 II- U Jan. 8, 1957 Filed May 4, 1955 D. s. CAMPBELL 2,7 76,759

RUBBER DRAFT GEAR 4 Sheets-Sheet 2 IN VEN TOR.

4 Sheets-Sheet 3 w IH M I MHIIMKI a H a 3 O 2 MW Iii 0 71 4 v /a3 0 WW 2 n a I NVENTOR- S. CA

RUBBER DRAFT GEAR Jan- Filed May 1955 Jan. 8, 1957 D. s. CAMPBELL 2,776,759

RUBBER DRAFT GEAR Filed May 4. 1953 4 Sheets-Sheet 4 RUBBER DRAFT GEAR DavidSi Campbell, 'Glen Ellyn, 111., assignorto 'Cardwe'll wes'tinghouse'fiompany, a corporation of Delaware Application May 4, 1953, SerialNo. 352,751

Claims. (Cl. 213-34) fid States Pam- Further 'o'bje'ctan'd advantages :of the invention will "be apparent as the description is read in connection with the accompanying drawings, in which Fig. .1""is a horizontal section through familiar parts .of a" freight car showing the draft gear applied;

Fig. 2 is a vertical section of the same; Sis an 'enlargedfhorizontal section through the draft gear and portions of the draft rigging and center sills showing the draft gear in release;

IFig'. 4is3a similar section showing the draftgearcompressed in bud;

associated followers;

Figs. 6, 7,, and 8 arevertical sections on the lines 6 6,

-Fig. 9 'is a perspective view,o'f 'the draft gear housing;

'Fig. .lJO'is a perspective view of the thrust wedge; and

Fig. Tl is an exploded perspective view of the friction shoes and friction springs making up the friction means to absorb .recoilenergy. But these drawings .and :the vcorresponding description are for the purpose of illustrative disclosure only, .and are not intended to impose unnecessary limitations on the claims. C

In Figs. land 2, the draft. geanindicated generally at 10, is shown in the'fam'iliar surroundings of center sills 111, draft .gear lugs 12., draft yoke '13, coupler (butt or shank 14, draft-key 15, coupler carrier iron 16, draft gear carrier iron 17, coupler horn 18, and striking plate 19 (all corresponding to Fig. 10.51 of Car Builders Cyclopedia, 1946, p. 944). These parts are so familiar that no specific description is deemed necessary.

The draft gear housing generally indicated by 20 includes a bottom 21 with the mid portion removed, a rear wall 22, spaced side walls 23, a hollow front wall 24 having an intermediate opening 25 through it, and friction shoe pockets 26 at each side of the intermediate opening 25.

The top of the housing is almost entirely omitted be 2 ates withza follower 32 in the front end of the housing '20 adjacent to the-front wall.

A thrust wedge 33 passing through the intermediate opening '25 cooperates with the 'fo'llower32 to deliver the thrust of the front standard follower .34 received from the coupler butt in bud. A rear standard follower 35 is between the rear wall .22 of. the housing .and'ithe rear draft gear lngs 12;

In each of the friction shoe pockets '26, there is a pair of 'triangular wedge shoes 38' urged toward the thrust 'wedge by a rubber spring 39', as seen particularly well in Figs. 3 and 4.

In assembly, the several parts of the cushioning element are dropped into place through the open top of the "housing 22, and come to rest on'the side portions 21 of the bottom. Th61fdllOW6r'32 is inserted between the front 'wall andthe front of the cushioning element. 'The rubber friction springs 3'9 and the'wedge shoes 38. are in- 'serted in .thefriction shoe pockets, .and the thrust wedge inserted through the intermediate opening 25 in the front wall '24.

The gear is "then put under initial compression in a suitable jig, and "afishear pin ,or pins 40 inserted through aligned openings 41 and 42 inthe front wall 24 and the adjacentwalls of the thrust wedge 33. In this condition, the draft gear forms a commercial article readily handled,

' -stored, andshipped, and under sufiicient initial comprestween the sides and ends except for an overhanging por- The rear end of the cushioning element 28 seats against the rear wall 22. The front end of the element coopercushioning element.

'Under compression, the wedge 33 in "cooperation with the shoes 38 functions-"as a friction gear supplementing the absorption of the rubber :cushioning element, and the friction increases "as *the gear closes, thereby providing increasedabsorption as the rebound is increased by the ilistortion of 'the rubber blocks.

lnone form that has been found satisfactory in seryice, the thrust' wedge 33"has atwo-degree taper, and the wedge shoes-"a thirty-degree taper with their dimensions lengthwise to the car on the order of /j shorter than the width of *the fric'tion shoe "pockets '26.

The draft gear housing is 115% long, and the thrust wedge is 7% long. 'Qther dimensions are substantially in proportion.

The cushion element, of course, is designed variously according to the capacity desired for the gear.

I claim:

1. In a draft gear, a housing including a bottom, a rear wall, spaced side walls, and a hollow front wall having an intermediate opening through it and friction I against the follower and extending through the intermediate opening in the front wall, friction shoes in said friction shoe pockets cooperating with said thrust wedge, and spring means urging the friction shoes against said thrust wedge. I

2. In a draft gear, a housing including a bottom, a rear wall, spaced side walls, and a hollow front wall having an intermediate opening through it and friction shoe pockets at each side of the intermediate opening, a cushioning element of the rubber spring type in said housing, a follower between the front wall and the cushioning element, a thrust wedge having one end hearing against the follower and extending through the intermediate opening in the front wall, pairs of wedge friction shoes in said friction shoe pockets cooperating with the said thrust wedge, and spring means urging the friction shoes against said thrust wedge.

3. In a draft gear, a housing including a bottom wall open through the mid portion, a rear wall, spaced side walls, and a hollow front wall having an intermediate opening through it for a thrust wedge and having pockets at each side of the intermediate opening for friction devices, a cushioning element including a plurality of rubber blocks and plates in said housing supported by said bottom wall and reacting at one end against said rear wall, a thrust wedge bearing against the other end of the cushioning element through the intermediate opening in the front wall, friction shoes in the friction shoe pockets cooperating with the thrust wedge, and spring means urging said friction shoes against the thrust wedge.

4. In a draft gear, front and rear followers engageable respectively with the spaced front and rear draft gear lugs of a railroad car center sill construction, the combination of cushioning and friction means disposed in the space between said followers comprising a housing shorter than said space including a closed rear wall engaged with the rear follower and a front wall having a central lengthwise opening and friction shoe pockets at the sides of said opening and communicating therewith, spring means in said housing, a thrust wedge extending through said central lengthwise opening having its ends reacting against the front follower and the spring means respectively, and friction shoes in said friction shoe pockets frictionally bearing against the sides of said thrust wedge for resisting movement of the thrust wedge through said central lengthwise opening at all times on compression or expansion of said spring means.

5. In a draft gear, front and rear followers engageable respectively with the spaced front and rear draft gear lugs of a railroad car center sill construction, the combination of cushioning and friction means disposed in the space between said followers comprising a housing shorter than said space including a closed rear wall engaged with the rear follower and a front wall having a central lengthwise opening and friction shoe pockets at the sides of said opening and communicating therewith, a front plate within said housing, spring means in the housing reacting between the rear wall thereof and said front plate, a thrust wedge extending through said central lengthwise opening having its ends bearing against the front follower and said front plate respectively, and friction shoes in said friction shoe pockets frictionally bearing against the sides of said thrust wedge for resisting movement of the thrust wedge through said central lengthwise opening at all times on compression or expansion of said spring means.

6. In a draft gear, a housing including a bottom, a rear wall, spaced side walls, and a hollow front wall having an intermediate opening through it and friction shoe pockets at each side of the intermediate opening, a cushioning element in said housing reacting against the front and rear walls thereof, a thrust member having one end reacting against the cushioning element and extending through the intermediate opening in the front wall, friction shoe means in said friction shoe pockets cooperating with said thrust member, and spring-like means urging the friction shoes against said thrust member.

7. A draft gear as claimed in claim 6 wherein the thrust member is wedge-shaped and the cushioning element is of the rubber spring type.

8. In a draft gear for mounting in the, draft pocket of a railway car, said pocket having spaced front and rear lugs; a housing longitudinally movable in said draft pocket and including a closed rear wall reacting against said rear lugs, a front wall having a central lengthwise opening and friction shoe pockets at the sides of said opening and communicating therewith, spring means in the housing reacting against the front and rear walls thereof, a thrust member having one end reacting against the said spring means and extending through the opening in the front wall such that its other end reacts against the front lugs, and friction shoe means in said friction shoe pockets frictionally bearing against the sides of said thrust member to resist movement of the thrust member through said central lengthwise opening at all times on compression or expansion of said spring means.

9. A draft gear as claimed in claim 8 wherein the thrust member is wedge-shaped and the spring means is of the rubber spring type.

10. In a draft gear, in combination: A cushioning unit of the rubber spring type, an energy absorbing friction References Cited in the file of this patent UNITED STATES PATENTS Kelso Dec. 23, 1902 Barrows June 3, 1930 yak 

